package com.atguigu.netty.heartbeat;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
import io.netty.handler.timeout.IdleStateHandler;

import java.util.concurrent.TimeUnit;

public class MyServer {

    public static void main(String[] args) throws Exception {

        // 创建两个线程组
        EventLoopGroup bossGroup = new NioEventLoopGroup(1);
        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try {
            ServerBootstrap serverBootstrap = new ServerBootstrap();

            serverBootstrap.group(bossGroup, workerGroup);
            serverBootstrap.channel(NioServerSocketChannel.class);
            serverBootstrap.handler(new LoggingHandler(LogLevel.INFO));
            serverBootstrap.childHandler(new ChannelInitializer<SocketChannel>() {

                @Override
                protected void initChannel(SocketChannel ch) {
                    ChannelPipeline pipeline = ch.pipeline();
                    // 加入一个netty 提供 IdleStateHandler
                    /*
                     * 说明
                     * 1. IdleStateHandler 是netty 提供的处理空闲状态的处理器
                     * 2. long readerIdleTime：表示多长时间没有读, 就会发送一个心跳检测包检测是否连接
                     * 3. long writerIdleTime：表示多长时间没有写, 就会发送一个心跳检测包检测是否连接
                     * 4. long allIdleTime：表示多长时间没有读写, 就会发送一个心跳检测包检测是否连接
                     * 5. 文档说明：triggers an {@link IdleStateEvent} when a {@link Channel} has not performed read, write, or both operation for a while.
                     * 6. 当 IdleStateEvent 触发后 , 就会传递给管道的下一个handler去处理，通过调用(触发)下一个handler 的 userEventTriggered，在该方法中去处理 IdleStateEvent(读空闲，写空闲，读写空闲)
                     */
                    pipeline.addLast(new IdleStateHandler(7000, 7000, 10, TimeUnit.SECONDS));
                    // 加入一个对空闲检测进一步处理的handler(自定义)
                    pipeline.addLast(new MyServerHandler());
                }
            });

            // 启动服务器
            ChannelFuture channelFuture = serverBootstrap.bind(7000).sync();
            channelFuture.channel().closeFuture().sync();

        } finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
}
